/* =========================================================
   /assets/site.css — 必一体育 共享样式
   竞技场深蓝 + 荧光青 + 琥珀金 + 暖橙 · 技术蓝图式轨道
   ========================================================= */

/* ---------- reset ---------- */
*,
*::before,
*::after { box-sizing: border-box; }

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body,
h1, h2, h3, h4, h5, h6,
p, ul, ol, li, figure, figcaption,
blockquote, dl, dt, dd {
  margin: 0;
}

ul, ol {
  padding: 0;
  list-style: none;
}

img, svg, picture {
  display: block;
  max-width: 100%;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  cursor: pointer;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ---------- tokens ---------- */
:root {
  /* 色彩 */
  --arena: #071426;
  --panel: #0E223B;
  --panel-2: #102A47;
  --grid: #183A5A;
  --cyan: #35E0D0;
  --gold: #FFC24A;
  --orange: #FF7A3D;
  --ice: #EAF6FF;
  --mist: #8FA6B8;
  --go: #5BE38A;
  --coral: #FF5C7A;
  --paper: #F4F7FA;
  --ink: #0C1B2A;
  --grid-ink: #4A6E8E;

  /* 结构 */
  --rail-w: 19rem;
  --topbar-h: 3.75rem;
  --wrap-max: 76rem;

  /* 字体 */
  --font-sans: "Noto Sans SC", "Source Han Sans SC", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;
  --font-mono: "JetBrains Mono", "IBM Plex Mono", ui-monospace, SFMono-Regular,
    Menlo, Consolas, "Liberation Mono", monospace;

  --fs-display: clamp(2rem, 1.1rem + 3.6vw, 4.25rem);
  --fs-h2: clamp(1.5rem, 1.1rem + 1.5vw, 2.35rem);
  --fs-h3: clamp(1.1rem, 1rem + 0.6vw, 1.4rem);
  --fs-body: clamp(1rem, 0.96rem + 0.18vw, 1.125rem);
  --fs-small: 0.8125rem;
  --fs-num: clamp(1.75rem, 1.1rem + 2.4vw, 2.75rem);

  /* 形状与动效 */
  --radius-lg: 1.25rem;
  --radius-md: 0.875rem;
  --radius-sm: 0.5rem;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
  --dur: 0.28s;

  --scroll-progress: 0;
}

/* ---------- base ---------- */
body {
  min-height: 100vh;
  padding-left: var(--rail-w);
  background-color: var(--arena);
  background-image:
    linear-gradient(to right, rgba(24, 58, 90, 0.34) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(24, 58, 90, 0.34) 1px, transparent 1px);
  background-size: 72px 72px;
  color: var(--ice);
  font-family: var(--font-sans);
  font-size: var(--fs-body);
  line-height: 1.75;
  overflow-x: hidden;
}

#main-content {
  scroll-margin-top: 1.5rem;
}

::selection {
  background: var(--cyan);
  color: var(--arena);
}

:where(a, button, input, textarea, select, [tabindex]):focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
  border-radius: 0.3rem;
}

/* ---------- skip link ---------- */
.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 300;
  padding: 0.6rem 1.1rem;
  border-radius: var(--radius-sm);
  background: var(--gold);
  color: #08121f;
  font-weight: 700;
  font-size: 0.9375rem;
  transform: translateY(-180%);
  transition: transform 0.2s var(--ease);
}

.skip-link:focus-visible,
.skip-link:focus {
  transform: translateY(0);
}

/* ---------- 品牌 ---------- */
.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  min-width: 0;
}

.brand__mark {
  flex: none;
  display: grid;
  place-items: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 0.7rem;
  background: linear-gradient(150deg, var(--gold), var(--orange));
  color: #08121f;
  font-family: var(--font-mono);
  font-size: 1.05rem;
  font-weight: 700;
  box-shadow: 0 0 0 1px rgba(255, 194, 74, 0.35),
    0 10px 26px -14px var(--gold);
}

.brand__text {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  min-width: 0;
}

.brand__name {
  font-size: 1.0625rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--ice);
  line-height: 1.3;
}

.brand__line {
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--mist);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.brand--footer .brand__mark {
  width: 2.75rem;
  height: 2.75rem;
  font-size: 1.2rem;
}

.brand--footer .brand__name {
  font-size: 1.15rem;
}

/* =========================================================
   HEADER — 侧边轨道
   ========================================================= */
.site-header {
  position: fixed;
  top: 0;
  bottom: 0;
  left: 0;
  z-index: 100;
  width: var(--rail-w);
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
  padding: 1.6rem 1.35rem 1.35rem;
  border-right: 1px solid var(--grid);
  background:
    radial-gradient(120% 60% at 0% 0%, rgba(53, 224, 208, 0.09), transparent 70%),
    linear-gradient(180deg, #0a1b30 0%, #071426 55%, #050f1c 100%);
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--grid) transparent;
}

.site-header::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  right: 0;
  width: 1px;
  background: linear-gradient(180deg, transparent, var(--cyan), transparent);
  opacity: 0.35;
  pointer-events: none;
}

/* 滚动进度光带 */
.rail-progress {
  position: fixed;
  top: 0;
  bottom: 0;
  left: calc(var(--rail-w) - 2px);
  z-index: 120;
  width: 2px;
  background: rgba(53, 224, 208, 0.1);
  pointer-events: none;
}

.rail-progress__fill {
  display: block;
  width: 100%;
  height: 100%;
  transform: scaleY(var(--scroll-progress));
  transform-origin: top center;
  background: linear-gradient(180deg, var(--cyan), var(--gold));
}

/* 品牌行 */
.rail-brand {
  display: flex;
  align-items: center;
  gap: 1rem;
}

/* 移动菜单按钮 */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 0.55rem;
  flex: none;
  padding: 0.5rem 0.8rem;
  border-radius: 0.6rem;
  border: 1px solid rgba(53, 224, 208, 0.4);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  transition: background var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}

.nav-toggle:hover {
  background: rgba(53, 224, 208, 0.12);
}

.nav-toggle__bars {
  display: flex;
  flex-direction: column;
  gap: 0.28rem;
  width: 1.05rem;
}

.nav-toggle__bars span {
  display: block;
  height: 1.5px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease);
}

.nav-toggle__text {
  line-height: 1;
}

/* 轨道面板 */
.rail-panel {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: 1.35rem;
  min-height: 0;
}

/* 导航 */
.rail-nav__label {
  margin-bottom: 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.24em;
  color: var(--grid-ink);
}

.rail-nav__list {
  counter-reset: rail;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.rail-nav__item {
  counter-increment: rail;
}

.rail-nav__link {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.5rem 0.65rem 0.5rem 0.6rem;
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  color: var(--mist);
  font-size: 0.9375rem;
  font-weight: 500;
  line-height: 1.5;
  transition: color var(--dur) var(--ease),
    background var(--dur) var(--ease),
    border-color var(--dur) var(--ease);
}

.rail-nav__link::before {
  content: counter(rail, decimal-leading-zero);
  flex: none;
  min-width: 1.15rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.05em;
  color: #3f6382;
  transition: color var(--dur) var(--ease);
}

.rail-nav__link:hover {
  color: var(--ice);
  background: rgba(53, 224, 208, 0.08);
  border-left-color: rgba(53, 224, 208, 0.5);
}

.rail-nav__link:hover::before {
  color: var(--cyan);
}

.rail-nav__link[aria-current="page"] {
  color: var(--ice);
  font-weight: 700;
  background: rgba(53, 224, 208, 0.13);
  border-left-color: var(--cyan);
}

.rail-nav__link[aria-current="page"]::before {
  color: var(--gold);
}

/* 轨内信息带 */
.rail-band {
  padding: 0.7rem 0.75rem 0.8rem;
  border: 1px dashed rgba(255, 122, 61, 0.4);
  border-radius: var(--radius-md);
  background: rgba(255, 122, 61, 0.05);
}

.rail-band__title {
  margin-bottom: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--orange);
}

.rail-band__list {
  display: grid;
  gap: 0.35rem;
}

.rail-band__cell {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.4rem 0.6rem;
  border: 1px solid rgba(255, 122, 61, 0.26);
  border-radius: 0.45rem;
  background: rgba(255, 122, 61, 0.1);
  color: #ffd9c2;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
}

.rail-band__cell::before {
  content: "";
  flex: none;
  width: 0.35rem;
  height: 0.35rem;
  border-radius: 1px;
  background: var(--orange);
}

.rail-actions {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.rail-note {
  margin-top: auto;
  padding-top: 0.85rem;
  border-top: 1px solid var(--grid);
  font-size: 0.72rem;
  line-height: 1.65;
  color: var(--mist);
}

.rail-note__code {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
  color: var(--gold);
}

/* =========================================================
   按钮
   ========================================================= */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.15rem;
  border: 1px solid transparent;
  border-radius: 0.7rem;
  font-family: var(--font-sans);
  font-size: 0.9375rem;
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1.3;
  text-align: center;
  cursor: pointer;
  transition: background var(--dur) var(--ease),
    color var(--dur) var(--ease),
    border-color var(--dur) var(--ease),
    box-shadow var(--dur) var(--ease),
    transform var(--dur) var(--ease);
}

.btn:active {
  transform: translateY(1px);
}

.btn--cyan {
  background: rgba(53, 224, 208, 0.12);
  border-color: rgba(53, 224, 208, 0.45);
  color: var(--cyan);
}

.btn--cyan:hover {
  background: var(--cyan);
  border-color: var(--cyan);
  color: #05202a;
  box-shadow: 0 16px 32px -20px var(--cyan);
}

.btn--gold {
  background: var(--gold);
  border-color: var(--gold);
  color: #08121f;
  box-shadow: 0 16px 32px -20px var(--gold);
}

.btn--gold:hover {
  background: #ffd67d;
  border-color: #ffd67d;
}

.btn--ghost {
  background: transparent;
  border-color: var(--grid);
  color: var(--ice);
}

.btn--ghost:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.btn--block {
  width: 100%;
}

/* =========================================================
   FOOTER
   ========================================================= */
.site-footer {
  position: relative;
  margin-top: clamp(3rem, 8vw, 6rem);
  border-top: 1px solid var(--grid);
  background: linear-gradient(180deg, #061120 0%, #040b15 100%);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: linear-gradient(
    to right,
    rgba(24, 58, 90, 0.38) 1px,
    transparent 1px
  );
  background-size: 96px 100%;
  opacity: 0.7;
  pointer-events: none;
}

.footer-strip {
  position: relative;
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 1.6rem;
  padding: 0.85rem clamp(1rem, 4vw, 3rem);
  border-bottom: 1px solid rgba(24, 58, 90, 0.9);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.2em;
  color: #5e86a8;
  text-transform: uppercase;
}

.footer-strip__item {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-strip__item::before {
  content: "";
  width: 0.9rem;
  height: 1px;
  background: var(--gold);
}

.footer-inner {
  position: relative;
  max-width: 78rem;
  margin-inline: auto;
  padding: clamp(2.25rem, 5vw, 3.75rem) clamp(1rem, 4vw, 3rem) 1.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.25rem;
}

.footer-brand__summary {
  margin-top: 1rem;
  max-width: 32ch;
  font-size: 0.9rem;
  line-height: 1.75;
  color: #a9c1d6;
}

.footer-brand__note {
  margin-top: 0.65rem;
  max-width: 34ch;
  font-size: 0.78rem;
  line-height: 1.7;
  color: var(--mist);
}

.footer-col__title {
  margin-bottom: 0.9rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  color: var(--cyan);
}

.footer-col__list {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.footer-col__list a {
  display: inline-block;
  color: var(--mist);
  font-size: 0.9375rem;
  line-height: 1.6;
  transition: color var(--dur) var(--ease),
    padding-left var(--dur) var(--ease);
}

.footer-col__list a:hover {
  color: var(--ice);
  padding-left: 0.3rem;
}

.footer-contact__line {
  margin-top: 0.55rem;
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--mist);
}

.footer-contact__value {
  display: block;
  margin-top: 0.1rem;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.02em;
  color: var(--ice);
  word-break: break-word;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: space-between;
  gap: 0.6rem 1.5rem;
  margin-top: 2.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid rgba(24, 58, 90, 0.9);
  font-size: 0.78rem;
  color: #5e86a8;
}

.footer-copy,
.footer-icp {
  font-family: var(--font-mono);
  letter-spacing: 0.06em;
}

/* =========================================================
   通用组件
   ========================================================= */
.wrap {
  width: min(100% - 2.5rem, var(--wrap-max));
  margin-inline: auto;
}

.kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--cyan);
}

.kicker::before {
  content: "";
  width: 1.75rem;
  height: 1px;
  background: currentColor;
}

.display {
  font-size: var(--fs-display);
  font-weight: 800;
  line-height: 1.04;
  letter-spacing: -0.02em;
  color: var(--ice);
}

.section-title {
  font-size: var(--fs-h2);
  font-weight: 800;
  line-height: 1.18;
  letter-spacing: -0.01em;
  color: var(--ice);
}

.lede {
  max-width: 52ch;
  font-size: clamp(1rem, 0.95rem + 0.4vw, 1.2rem);
  line-height: 1.78;
  color: #b9cee0;
}

.rule {
  height: 1px;
  border: 0;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(24, 58, 90, 1) 12%,
    rgba(24, 58, 90, 1) 88%,
    transparent
  );
}

.panel {
  padding: clamp(1.25rem, 3vw, 2rem);
  border: 1px solid rgba(24, 58, 90, 0.95);
  border-radius: var(--radius-lg);
  background: linear-gradient(
    160deg,
    rgba(14, 34, 59, 0.96),
    rgba(9, 23, 40, 0.96)
  );
}

/* 页面版首屏信息带 */
.info-band {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
  gap: 1px;
  border: 1px solid rgba(255, 122, 61, 0.35);
  border-radius: var(--radius-lg);
  background: rgba(255, 122, 61, 0.35);
  overflow: hidden;
}

.info-band__cell {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  padding: 1.15rem 1.25rem;
  background: #0b1e34;
}

.info-band__label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.18em;
  color: var(--orange);
}

.info-band__value {
  font-family: var(--font-mono);
  font-size: var(--fs-num);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.01em;
  color: var(--ice);
}

.info-band__unit {
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.info-band__cell--accent .info-band__value {
  color: var(--gold);
}

/* 标签 */
.tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.22rem 0.6rem;
  border: 1px solid var(--grid);
  border-radius: 999px;
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  color: var(--mist);
}

.tag--cyan {
  border-color: rgba(53, 224, 208, 0.45);
  background: rgba(53, 224, 208, 0.09);
  color: var(--cyan);
}

.tag--gold {
  border-color: rgba(255, 194, 74, 0.45);
  background: rgba(255, 194, 74, 0.09);
  color: var(--gold);
}

.tag--go {
  border-color: rgba(91, 227, 138, 0.45);
  background: rgba(91, 227, 138, 0.09);
  color: var(--go);
}

.tag--coral {
  border-color: rgba(255, 92, 122, 0.45);
  background: rgba(255, 92, 122, 0.09);
  color: var(--coral);
}

/* 面包屑 */
.breadcrumbs {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
  color: var(--mist);
}

.breadcrumbs ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.4rem;
}

.breadcrumbs li {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.breadcrumbs li + li::before {
  content: "/";
  color: var(--grid);
}

.breadcrumbs a {
  transition: color var(--dur) var(--ease);
}

.breadcrumbs a:hover {
  color: var(--cyan);
}

.breadcrumbs [aria-current="page"] {
  color: var(--ice);
}

/* 纵向注释 */
.note-vertical {
  writing-mode: vertical-rl;
  font-family: var(--font-mono);
  font-size: 0.66rem;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--grid-ink);
}

/* 图片容器 */
.img-frame {
  position: relative;
  display: block;
  overflow: hidden;
  border: 1px solid rgba(24, 58, 90, 0.95);
  border-radius: var(--radius-lg);
  background: linear-gradient(150deg, #0e223b, #0a1a2e);
  aspect-ratio: 16 / 10;
}

.img-frame::before {
  content: "";
  position: absolute;
  top: 0.7rem;
  right: 0.7rem;
  z-index: 1;
  width: 1.25rem;
  height: 1.25rem;
  border-top: 1px solid var(--cyan);
  border-right: 1px solid var(--cyan);
  opacity: 0.7;
  pointer-events: none;
}

.img-frame img,
.img-frame picture,
.img-frame > picture > img,
.img-frame svg {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.img-frame--wide {
  aspect-ratio: 21 / 9;
}

.img-frame--tall {
  aspect-ratio: 3 / 4;
}

.img-frame--square {
  aspect-ratio: 1 / 1;
}

.img-frame__caption {
  position: absolute;
  left: 0;
  bottom: 0;
  z-index: 1;
  padding: 0.7rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  letter-spacing: 0.16em;
  color: var(--ice);
  text-shadow: 0 1px 8px rgba(4, 11, 21, 0.9);
}

/* 返回顶部（JS 注入） */
.to-top {
  position: fixed;
  right: 1.25rem;
  bottom: 1.25rem;
  z-index: 130;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.7rem 1rem;
  border: 1px solid rgba(53, 224, 208, 0.45);
  border-radius: 999px;
  background: rgba(9, 23, 40, 0.92);
  color: var(--cyan);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity var(--dur) var(--ease),
    transform var(--dur) var(--ease),
    background var(--dur) var(--ease),
    color var(--dur) var(--ease),
    visibility var(--dur) var(--ease);
}

.to-top[data-visible="true"] {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  pointer-events: auto;
}

.to-top:hover {
  background: var(--cyan);
  color: #05202a;
}

/* =========================================================
   响应式
   ========================================================= */

/* 页脚双栏（平板） */
@media (min-width: 40rem) {
  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 2.25rem 1.75rem;
  }

  .footer-brand {
    grid-column: 1 / -1;
  }
}

/* 桌面：页脚四栏 */
@media (min-width: 64rem) {
  .footer-grid {
    grid-template-columns: 1.55fr 1fr 1fr 1.25fr;
    gap: 2.5rem;
  }

  .footer-brand {
    grid-column: auto;
  }
}

/* 移动 / 平板：头部改为顶部条 + 抽屉 */
@media (max-width: 63.9375rem) {
  body {
    padding-left: 0;
    padding-top: var(--topbar-h);
  }

  body.nav-open {
    overflow: hidden;
  }

  #main-content {
    scroll-margin-top: calc(var(--topbar-h) + 1rem);
  }

  .site-header {
    top: 0;
    right: 0;
    bottom: auto;
    left: 0;
    width: auto;
    height: auto;
    gap: 0;
    padding: 0;
    border-right: 0;
    border-bottom: 1px solid var(--grid);
    background: #08182b;
    overflow: visible;
  }

  .site-header::after {
    display: none;
  }

  .rail-progress {
    top: calc(var(--topbar-h) - 2px);
    right: 0;
    bottom: auto;
    left: 0;
    width: auto;
    height: 2px;
  }

  .rail-progress__fill {
    width: 100%;
    height: 100%;
    transform: scaleX(var(--scroll-progress));
    transform-origin: left center;
    background: linear-gradient(90deg, var(--cyan), var(--gold));
  }

  .rail-brand {
    justify-content: space-between;
    min-height: var(--topbar-h);
    padding: 0.6rem 1rem;
  }

  .brand__line {
    font-size: 0.66rem;
    letter-spacing: 0.05em;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .rail-panel {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    display: block;
    max-height: 0;
    padding: 0 1rem;
    border-bottom: 1px solid transparent;
    background: #08182b;
    overflow: hidden;
    visibility: hidden;
    transition: max-height var(--dur) var(--ease),
      visibility var(--dur) var(--ease),
      border-color var(--dur) var(--ease);
  }

  .rail-panel > * + * {
    margin-top: 1.15rem;
  }

  .site-header[data-open="true"] .rail-panel {
    max-height: calc(100vh - var(--topbar-h));
    padding-bottom: 1.35rem;
    border-bottom-color: var(--grid);
    overflow-y: auto;
    visibility: visible;
  }

  .site-header[data-open="true"] .nav-toggle__bars span:nth-child(1) {
    transform: translateY(0.21rem) rotate(45deg);
  }

  .site-header[data-open="true"] .nav-toggle__bars span:nth-child(2) {
    transform: translateY(-0.21rem) rotate(-45deg);
  }

  .rail-nav__list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
    gap: 0.2rem;
  }

  .rail-nav__link {
    font-size: 0.9375rem;
    padding-block: 0.6rem;
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  }

  .rail-band__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .rail-band__cell {
    justify-content: center;
    font-size: 0.75rem;
  }

  .rail-actions {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .rail-actions .btn {
    flex: 1 1 9rem;
    width: auto;
  }

  .rail-note {
    margin-top: 1rem;
    padding-top: 0.85rem;
  }

  .to-top {
    right: 0.9rem;
    bottom: 0.9rem;
  }
}

@media (max-width: 30rem) {
  .rail-band__list {
    grid-template-columns: 1fr;
  }

  .brand__line {
    display: none;
  }

  .footer-strip {
    letter-spacing: 0.12em;
  }
}

/* 减少动效 */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}